1. Field of the Invention
The invention relates to a device for discharging clinker, and more particularly to a device that discharges the bottom ash from the coal-fired boilers.
2. Description of the Related Art
Conventional coal-fired boilers of power plants mainly utilize a wet-type bottom ash handling system/device and a dry-type bottom ash handling system/device.
For the wet-type bottom ash handling system, most of the high temperature big lumps and large clinkers may drop into water and then become granulated into smaller ones for convenient delivery.
However, there are some disadvantages with the wet-type bottom ash handling system, provided as below:                (1) The fact that the clinker drops from the bottom of the boiler directly into the cooling water may cause a waste of the combustible material in the clinker and a loss of physical heat, in addition, the generated steam may corrode the components installed at the bottom of the boiler.        (2) Much water is consumed, and the environment is polluted by the discharged waste water, which may lead to high disposal cost.        (3) The system is complicated and may cause high maintenance and repair cost.        
Therefore, dry-type bottom ash handling technology is the most widely used technology at present. However, the granulation by water is not involved in the dry-type bottom ash handling equipment and thus large clinkers are generated, which may destroy the steel belt of the crusher if the clinker directly falls onto the steel belt, and various-size bottom ash may enter the crusher, thereby increasing the workload of crusher and causing low efficiency and high malfunction rate.
In practice, the bottom ash handling system may stop running, because the crusher is sometimes jammed by clinkers or overloaded, or the clinkers are too hard to crush, or even its chain becomes broken.
To solve the above problems, a dry-type conveying device for high temperature bottom ash of coal-fired boilers is disclosed. The device includes a steel belt conveyer, a hydraulic clinker crusher and impact bars installed above the conveyer, and the impact bars are installed underneath the hydraulic clinker crusher. The hydraulic clinker crusher and the impact bars are supported by the clinker case, and the upper portion of clinker case is connected with the bottom ash hopper outlet installed at the bottom of the coal-fire boiler, and the lower portion of clinker case is connected with the top of the steel belt conveyer. The impact bars are composed of a plurality of heat-resistant metal rods, two ends of the heat-resistant metal rod supported by the clinker case are respectively connected with a cooling water pipe, the metal rods of the impact bars are used as the guide rail of the clinker crushing body of the hydraulic clinker crusher, the contact portion of the clinker crushing body and the impact bars is wave-shaped, and the clinker crushing body has a form of jaw that engages with each other. The disposal of the clinker crusher and the impact bars at the bottom of coal-fired boiler prevents the large clinker from directly dropping onto the conveying belt, thereby avoiding the damage of the conveying belt, reducing the crushing workload, and increasing the service life of the clinker crusher and even the whole device.
However, the above-motioned high temperature dry-type bottom ash conveying device still has some disadvantages:                (1) In the above-motioned high temperature dry-type bottom ash conveying device, a portion of bottom ash from the outlet of the bottom ash hopper will not drop into the area where the clinker crushing body of the hydraulic clinker crusher is working, however, it may affect the normal working of the clinker crushing body if too much bottom ash is accumulated in this area.        (2) As the impact bars are fixed on the clinker case, once the impact bars are damaged or destroyed, the device has to be stopped working for repair or replacement, which may have bad influence on the normal power generation of the power plant.        (3) The fact that the clinker crushing body is the form of jaw that engages with each other, i.e. the cross section of the body is n-shaped, and the vertical section thereof is rectangle (referring to FIG. 1), so that large clinkers can be easily pushed to the cover instead of being impaled or penetrated by the clinker crushing body when the clinker crusher body is driven by the hydraulic cylinder with relative movement. Therefore, there may be lots of big-sized slag that are not crushed immediately, which may affect the efficiency of crushing.        